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<td class="header">&nbsp; Slice Assembly<br>
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<h3>Sentinel-1 Slice Assembly</h3>
<p class="MsoNormal">The SENTINEL-1 SAR is capable of operating up to 25 minutes
per orbit in any of the three high bit rate modes (SM, IW, EW). To avoid
distributing huge unwieldy products to end users, the Level-0 and Level-1
products are segmented into 'slices' of defined length along a track. Product
slices make the data more manageable for users and enable the ground segment to
process slice data in parallel.</p>

<p class="MsoNormal">Each product slice is a stand-alone product that can be
processed independently. Slices are ~25 seconds in length for SM and IW and ~60
seconds for EW. Each GeoTIFF band within a product slice will be no larger than
2 GB. However, since a product could contain several bands for swaths and
polarisations, the overall product size could be much larger.</p>

<p class="MsoNormal">WV data is not sliced and the full segment is processed into
Level-2.</p>

<p class="MsoNormal">Level-1 slice products are of seamless quality without any
data gap or duplicated lines and with no geometric, radiometric or phase
discontinuity. Sliced products may be seamlessly combined, including the
metadata, into an assembled product. Product assembly follows specific rules
for including, merging and concatenating the various components of the slice
products.</p>

<p class="MsoNormal">The amount of black-fill at near and far range of the
Level-1 image can vary with the segment length. The longer the segment the more
black-fill is potentially needed.</p>

<p class="MsoNormal">Slice products can be combined to form an assembled Level-1
product with the same product characteristics covering the complete segment.
Assembly is performed following the three strategies of Include, Merge and
Concatenate.</p>

<ul style="margin-top: 0cm;" type="disc"><li class="MsoNormal">Include - the value of the
     information is identical for all slices and a single occurrence of the
     value is copied into the assembled product.</li><li class="MsoNormal" style="">Merge - the value of the
     information may differ between slices and a single value must be
     amalgamated into the assembled product using the values from all slices.
     This can be accomplished by means of averaging, majority polling, summing,
     etc.</li><li class="MsoNormal">Concatenate - the
     information is stored in list format and the values from each slice are
     appended to the appropriate list in the assembled product in Zero Doppler
     Time (ZDT) ordered sequence and the list count attribute is updated to
     contain the number of items in the concatenated list. This applies to both
     binary image data and XML lists.</li></ul>


<h4>Input <br>
</h4>



<ul>
<li>The input to this operator should be a set (more than one) of Sentinel-1 slice products with consecutive slice numbers.<br>
  </li>
</ul>

<h4>Output <br>
</h4>




<ul>
<li>The output of the operator is the assembled Sentinuel-1 product. <br>

  </li>
</ul>


<h4>Parameters Used<br>
</h4>




<ul>
<li>Polarisations: The polarisations of the assembled product. User can select one or more polarisations.<br>
  </li>
</ul>


<p><img style="width: 650px; height: 500px;" alt="" src="images/SliceAssembly.jpg"><br>

</p>

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